Pirn



Oct. l, 1968 C, W|L| |AMSMET AL PIRN 2 Sheets-She l Filed Dec. 1, 1966 lnrvmrrofzs: THOMAS C. WILUAMS and ATTORNEYS Oct. l, 1968 13C, W|L| |AMS ET AL PIRN Filed Dec. 1, 1966 manna El? 2 Sheets-Sheet 2 IL im m 'I 'I l777 III THOMAS @.WnLmAMs ad.' FRAN K MAVH Ew Bymel/ ATTORNEYS United States Patent O 3,403,872 PIRN Thomas C. Williams, 1401 Cavendish Court, and Frank Mayhew, 4104 Providence Road, both of Charlotte, N.C. 28211 Filed Dec. 1, 1966, Ser. N0. 598,473 s C1aims.(Cl.z4z-11s.31)

ABSTRACT OF THE DISCLOSURE A pirn is formed as a lightweight one-piece body and is strengthened against radially directed compressive stress when yarn is wound thereon by a plurality of radially inwardly projecting internal reinforcing ribs circumferentially spaced apart within a central longitudinal cavity of the body. The internal reinforcing ribs taper longitudinally of the body in a predetermined manner from maximum dimensions intermediate t-he extremities of the pirn to minimum dimensions adjacent the ends of the pirn.

This invention relates to a pirn, and more particularly, to a lightweight pim which is strengthened against compressive stress exerted thereon when yarn is wound thereabout and which provides significant advantages in simplicity of construction and in costs of handling.

In certain segments of the textile industry, namely W-here artificial bers are used in the manufacture of textile products, textile yarn is frequently transported from a liber producer to a point of use in packages formed by winding the yarn about core forms known as bobbins or pirns. In such handling of textile yarn, such as nylon, pirns are continuously shuttled back and forth between fiber producers and fiber users, introducing two particular diiculties which have been heretofore apparent but without solution.

First, a pirn being transported back and forth between a fiber producer and a fiber user is repeatedly stressed by the winding and unwindin-g of yarn thereon. In winding or unwinding yarn on or from the pim under tension conditions, the tension forces acting on the wound yarn give rise to substantial radially inwardly directed compressive forces, which will crush a pirn not -designed to withstand forces of the magnitude generated. The necessity of providing a pim structure which will withstand repeated cycles of such stressing has heretofore resulted in the manufacture of pirns which are both expensive and of relatively heavy construction.

Secondly, the weight of the pim is a tare weight which must be freighted between the producer and user irrespective of the absence or presence of a net weight of yarn wound thereon. The freight charged merely for the transportation of empty pirns understandably is substantial where a number of pirns are transported.

With the aforementioned difficulties particularly in mind, it is an object of this invention to provide a pim which is sufficiently rugged to withstand the treatment to which such package cores are subjected while being of a substantially lighter weight than pirns heretofore known and used, so as to permit obtaining significant transportation cost savings. This object is realized in a lightweight pirn constructed as `a one-piece body Ihaving an exterior surface adapted for the winding of yarn thereon, dening a central longitudinal -cavity for receiving fa spindle on which the pim is mounted for packaging or unpackaging of yarn, and including 4a plurality of reinforcing ribs within the central cavity.

Some of the objects and -advantages of the invention having been stated, others will appear as the description proceeds, when taken in connection with the accompanying drawings, in which:

F IC@ FIGURE 1 is an elevation view of a pirn in accordance with this invention;

FIGURE 2 is a sectional view of the pim of FIG- URE l;

FIGURE 3 is an end view of the pirn of FIGURE 1, taken substantially as indicated by the arrow 3 in FIG- URE 2;

FIGURE 4 is a view similar to FIGURE 3, taken substantially as indicated by the arrow 4 in FIGURE 2;

FIGURE 5 s a sectional view of the pirn of FIGURE l, taken substantially 'as indicated by the line 5-5 in FIGURE 2;

FIGUR-E 6 is a perspective view, in partial section, of the pim of FIGURE l, taken substantially as indicated by the line 6 6 in FIGURE 1;

FIGURE 7 is an enlarged sectional view of a portion of the wall of the pirn of FIGURE 1, taken substantially as indicated by the line 7-7 in FIGURE 5;

FIGURE 8 is a sectional view of a portion of the wall `of the pirn of FIGURE 1, taken substantially as indicated by the line `8 8 in lFIGURE 7;

FIGURE 9 is a view, similar to FIGURE 1, of another pirn in accordance with this invention;

FIGURE 10 is a view, similar to FIGURE 2, of the pim of FIGURE 9;

FIGURE 11 is `a view, similar to FIGURE 3, of the pirn of FIGURE 9;

FIGURE 12 is Ia view, similar to FIGURE 4, pirn of FIGURE 9;

FIGURE 13 is Ia view, similar to FIGURE 5, pirn of FIGURE 9;

FIGUR-E 14 is a view, similar to FIGURE 6, pirn of FIGURE 9;

FIGURE 15 is a view, similar to FIGURE 7, pirn of FIGURE 9; and

FIGURE 16 is `a view, similar t0 FIGURE 8, pim of FIGURE 9.

Referring now more particularly to the drawings, the lightweight pirn of this invention is there shown, generally indicated at 10 (FIGURE l), and will be described more particularly hereinafter. While the pirn 10 is formed as a one-piece or single unitary body, that body includes a number of features which particularly distinguish the pim 10, which features will be individually identified and discussed hereinafter.

In order to provide for the packaging of textile yarn as described heretofore, the one-piece body of the pirn l10 is formed with a cylindrical exterior surface 11. Preferably, the exterior surface 11 is provided with a plurality of annular grooves 12 formed therein (FIGURES 7 and 8), for facilitating retention of textile yarn Wound on the pim 10. The body of the pirn 10 may also be provided with a thin surface coat 14 at the exterior surface 11, as will be mentioned hereinafter in a discussion of materials preferred in forming the pirn 10.

In order to provide for mounting of the pim 10 on the spindle of a textile machine during packaging or unpackaging of yarn wound about the exterior surface 11, this invention provides that the body of the pim 10 define a central longitudinal cavity, indicated generally at 15. The central longitudinal cavity 15 is open at both ends of the pirn 10, and the body of the pim defines therewithin a plurality of circumferentially spaced apart radially inwardly projecting internal reinforcing n'bs 16. Due to the particular construction of the reinforcing ribs 16, as will be discussed more fully hereinafter, the primary wall portions of the pirn 10, the outer surfaces of which define the exterior surface 11 of the pim, are relatively thin sections, as indicated at the line 7-7 in FIG- URE 5. This relatively thin section is, however, supported against the radially directed compressive forces exerted of the of the of the of the of the thereon by textile yarn, when the same is wound on the pirn under tension, by the ribs 16.

In packaging textile yarn on the pirn 10 by winding the same thereon under tension, the compressive forces exerted on the pirn are more intense at the medial portion of the length of the pirn. For this reason, among others, each of the reinforcing ribs 16 tapers longitudinally of the unitary body from a maximum circumferential and radial extent intermediate the extremities of the central cavity to a minimum circumferential and radial extent adjacent the ends of the body. The taper of the internal ribs 16 preferably is linear along the length of the body forming the pirn 10, so as to provide for ease in manufacturing the pirn 10 as will be described hereinafter.

In order to assure that the pirn 10 is properly positioned on the spindle of a textile machine for packaging or unpackaging of yarn wound thereabout, a bearing indicated generally at 18 is provided and located medially of the length of the central longitudinal cavity 1S. The spacing of the bearing 18 within the central cavity 15 and the diameter of the bearing 18 are such that the spindle engages the body forming the pirn 10 at the bearing 18 and the exterior surface 11 is maintained substantially concentric with the axis of rotation of the spindle. The bearing 18 may have a generally circular cross-sectional configuration (as shown) or some other configuration intended for mating cooperation with a particular spindle.

In order to provide for driving engagement of the pirn 10 with a whorl of a spindle, and thereby facilitate packaging or unpackaging of yarn wound about the pirn 10, one end of the unitary body forming the pirn 10 is provided with means, generally indicated at 19, for driving engagement with the whorl. While the means 19 may take any necessary form for cooperation with a particular whorl design, the means is formed integrally with the unitary body of the pirn 10, as by folding into the central longitudinal cavity 15 of a portion of the material adjacent one end of the pirn 10, to form within an otherwise open end of the pirn 10 a multilobed geometrical figure (FIGURE 4) or some other shape which matingly engages a whorl.

In order to assure obtaining the shipping cost benefits of low weight and to permit protection of the exterior surface 11 against nicking and scratching damage during stripping of residual amounts of yarn therefrom, the unitary body from which the pirn 10 is formed preferably is, in accordance with this invention, a lightweight anodically oxidizable metal or an alloy of such lightweight metals such as aluminum and magnesium. Such lightweight metals may be impact extruded ink a generally cylindrically-shaped die through the use of a pair of opposing extruding punches. In such a manufacturing procedure, the opposed extruding punches are each configured to shape a corresponding one of the rib-including portions of the central cavity 15 of the pirn 10. Thereafter, one end of the body may be cold-headed to form the whorl engaging means 19. When aluminum, magnesium or an alloy predominantly of those .metals is used as the material for the body of the pirn 10, a hard surface coating 11 may be formed thereon through anodizing.

Such an anodized layer 11 has a scratch hardness of approximately 9 on the Mohs scale, through being a predetermined density and thickness, and protects the exterior surface against nicks and scratches which otherwise would occur when a knife is used to cut residual amounts of yarn from the pirn 10.

While it is preferred, in accordance with the discussion given immediately above, to employ light metals or alloys of light metals in forming the unitary body of the pirn 10, is may be readily comprehended that molded plastic materials may also be used to form the unitary body of the pirn 10, and this invention comprehends such alternative materials.

A modified form of the pirn 10, described above, is shown in FIGURES 9 through 16 where corresponding elements of the pirn structure are identified by primed numerals similar to those used in FIGURES l through 8. In view of the close similarity of the pirn 10 shown in FIGURES 9 through 16 to the pirn 10 shown in FIG- URES l through 8, it is here considered appropriate merely to discuss the features which distinguish the modified pirn 10. .y

In certain circumstances, it may be considered appropriate to provide a material for bearing on the spindle other than the material forming the one-piece body of the pirn 10. In that event, a bearing insert 21 (FIGURES 10 and 14) is provided and fitted into the bearing portion `located medially of the central longitudinal cavity 15 of the pirn 10. The sleeve 21 inserted to thus engage a spindle preferably is formed of a suitable bearing material such as bronze or a lubricant permeated sintered metal.

The whorl engaging means 19 (FIGURE l2) is adapted for use with a spindle having a double lobed whorl. Such a whorl engaging means 19 is readily formed as an alternative to that shown in FIGURE 4.

In order to substantially close the central longitudinal cavity 15 of the pirn 10', and thus tend to reduce the accumulation of debris therein, the end of the pirn 10 opposite to that end provided with the whorl engaging means 19 is substantially closed (FIGURES l0, l1 and 14), by cold-heading the material forming the body 10 so as to form an end-closing Wall 22.

In the drawings and Specification, there have been set forth preferred embodiments of the invention, and although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being defined in the claims.

We claim:

1. A lightweight pirn strengthened against radially directed compressive stress when yarn is Wound thereon comprising a one-piece body having a cylindrical exterior surface adapted for the winding of yarn thereabout and defining a central longitudinal cavity with a plurality of radially inwardly projecting internal reinforcing ribs circumferentially spaced apart therewithin, a bearing located intermediate the extremities of said cavity, said internal ribs being tapered longitudinally of said body from a maximum circumferential width adjacent said bearing to a minimum circumferential width adjacent the ends of Said body, and means on the body for `driving engagement with a whorl of a spindle.

2. A pirn according to claim 1 Vwherein said internal ribs taper longitudinally of said body from a maximum radial thickness adjacent said bearing to a minimum radial thickness adjacent the ends of said body.

3. A pirn according to claim 2 wherein the taper of said internal ribs is linear.

4. A pirn according to claim 1 wherein said bearing includes a cylindrical insert of bearing material positioned therewithin and adapted for engagement with the spindle.

5. A pirn according to claim 1 wherein said means for whorl engagement comprises a terminal portion of said body at one end thereof defining an end wall at least partially occluding said cavity and configured for mating engagement with the whorl of the spindle.

6. A pirn according to claim 4 wherein a terminal portion of said body at one end thereof defines an end wall at least partially occluding said cavity.

7. A pirn according to claim 1 wherein said body is formed of an anodically oxidizable metal, a plurality of longitudinally spaced apart shallow annular grooves are formed in said cylindrical surface for facilitating retention of yarn wound thereon and a layer of anodically formed oxide on said cylindrical surface and having a thickness and density within predetermined limits protects said cylindrical surface against damage.

8. A lightweight pirn strengthened against radially directed compressive stress when yarn is wound thereon and protected against damage comprising a one-piece body of anodically oxidizable metal having a cylindrical exterior surface adapted for the Winding `of yarn thereabout and defining a central longitudinal cavity with a plurality of radially inwardly projecting internal reinforcing ribs circumferentially spaced apart therewithin, each of said ribs having a linear taper longitudinally of said body from a maximum circumferential width and radial thickness at a predetermined location intermediate the extremities of said cavity to a minimum circumferential width and radial thickness adjacent the ends of said body, said body including a bearing at said predetermined location within said cavity and means at one end of said body for driving engagement with a whorl of a spindle, and said body further including a plurality of longitudinally spaced apart shallow annular grooves for facilitating retention of yarn wound thereabout and a layer of anodically formed oxide formed on said cylindrical surface for protecting said cylindrical surface against damage.

References Cited UNITED STATES PATENTS 1,977,714 10/1934 Beran 242-118.4

2,463,484 3/ 1949 Gelpke 57-130 XR 2,615,650 10/1952 Betner et al. 242-118.32

3,248,070 4/ 1966 `lulien 242-1183 FOREIGN PATENTS 1,226,529 2/ 1960 France.

GEORGE F. MAUTZ, Primary Examiner. 

